The present invention relates generally to police radar/laser detectors, and more particularly, to displays for police radar/laser detectors.
Police traffic surveillance devices emit an electromagnetic signal in the radio frequency (RF) band or light band (i.e., infrared, visible, and ultraviolet light) that reflect off of approaching or departing vehicles to determine their speed. In particular, a change in frequency (Doppler shift) or a change in time of travel for return signal pulses is sensed for calculating vehicle speed.
Police radar and laser detectors (xe2x80x9cdetectorsxe2x80x9d) are used by drivers of vehicles to detect radiant electromagnetic signals characteristic of police traffic surveillance devices. In particular, the following RF (radar) frequency bands are used: X-band (10.525 GHzxc2x125 MHz); K-band (24.150 GHzxc2x1100 MHz); and Ka-band (34.700 GHzxc2x11300 MHz). Furthermore, laser wavelength of 904 nm with 33 MHz bandwidth is also used. These detectors are generally a detachable device clipped to a visor or dash of the vehicle for unimpeded sensing of the signals and for providing a conveniently positioned display and one or more controls to the driver. While police radar/laser detectors successfully provide alerts to the driver, generally during significant portions of time there are no alerts to be made. Consequently, the display capabilities of the detector are generally limited to displaying the operating mode (xe2x80x9cpilot modexe2x80x9d) of the detector. In addition to the under-utilized display, detectors increasingly use digital signal processors for processing received electromagnetic signals that operate faster with additional data and program storage capabilities. Consequently, the processing capacity of the detectors is also under-utilized much of the time. For example, detectors spend less than two percent of their operating time alerting the user of received electromagnetic signals.
Taking advantage of the unused capacity of a detector would increase its value. For instance, many drivers would benefit from the display of other sensed conditions associated with their vehicle. However, sensor displays integral to the vehicle instrument panel are either expensive or unavailable for certain models. Using after-market displays is inconvenient and tends to clutter the interior of the vehicle. Consequently, drivers often forego incorporating additional displays for sensed conditions.
Therefore, a significant need exists for a police radar/laser detector that incorporates additional sensing and display of conditions associated with a vehicle.
The present invention addresses these and other problems in the prior art by providing a police radar/laser detector that senses and displays a vehicle parameter, such as a sound pressure level, acceleration, etc. During those periods when the detector is not required to alert the driver of a police traffic surveillance device, the detector is configured to provide additional valuable information to the driver.
Consistent with one aspect of the invention, a detector and method of using a detector include a receiver that receives an electromagnetic signal emitted by a police traffic surveillance device. A controller responds to the received electromagnetic signal by initiating a visual and/or audible alert. The controller also responds to a sensed vehicle parameter by displaying the parameter when the alert is not present.
Consistent with an additional aspect of the invention, a detector similarly responds to sensed electromagnetic signal by initiating an alert. Advantageously, the detector includes a sensor for sensing sound pressure or acceleration. A controller is responsive to the sensor to display sound pressure or acceleration.
The above and other objects and advantages of the present invention shall be made apparent from the accompanying drawings and the description thereof.